Method and system for exploiting location-dependent services in a cellular radio system

ABSTRACT

A communications system ( 100, 300 ) comprises base stations ( 101 ) for providing mobile stations ( 104 ) with communications links. It comprises at least one localized service area ( 111 ) and means ( 108, 109 ) for changing the service selection offered to a given mobile station on the initiative of the communications system. The change is realized in response to information ( 203 ) indicating the arrival of the mobile station in said localized service area.

RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.13/072,443, filed Mar. 25, 2011, which is a continuation of U.S.application Ser. No. 09/646,802, filed Oct. 17, 2000, which is a U.S.National Stage of International PCT Application No. PCT/FI99/00227 filedon Mar. 23, 1999, and claims priority to Finnish Patent Application No.980654 filed Mar. 23, 1998; the entireties of which are incorporatedherein by reference.

FIELD OF THE INVENTION

The invention relates in general to the provision and delivery ofservices offered by a network to a mobile station. In particular theinvention relates to the utilization of information concerning thelocation of a mobile station for the purpose of providing services.

BACKGROUND OF THE INVENTION

A modem communications network provides mobile station owners withindividual programmable services. A digital telephone network is onesuch network. Services known to be provided by it include programmablecall transfer and voice mail system, which usually are implemented at aswitching center. Networks are also known in which certain services areprovided by an outside service provider who pays to the communicationsnetwork operator for the use of their network, and the services providedby said service provider are located physically elsewhere than atswitching centers. This patent application uses a digital cellular radiosystem as an example of a communications network.

In known networks the provision of services has not depended on the partof the network the user is located in when he places a call to anapparatus or equipment providing a service. According to a recentproposal, however, different locations can be specified for a mobilestation in a network. Then, as a mobile station is registered in a cell,the service that it receives may be different according to its location.However, it would be advantageous in various situations if differentservices could be offered to the user according to his physical locationon the initiative of the network, without the mobile station actuallyestablishing a connection to the net-work. Such services are callednetwork initiated services, and they include so-called push services inwhich an apparatus connected to the network sends data to mobilestations without the mobile stations requesting said information. Anexample of a locally arranged push service which cannot be implementedusing prior-art solutions is to send the day's menu at a cafeteria of acompany to the mobile stations of all those employees who are within thepremises of the company as lunchtime is approaching.

The reference publication CA 2,195,487 discloses the definition of aso-called user zone, which consists of one or more cells and/or cellsectors. It is on the responsibility of the mobile telephone switchingoffice (more commonly known as the MSC or Mobile services SwitchingCentre) to store the user zone profile and to modify a service profilefor a cellular telephone when that cellular telephone is situated withinthe user zone.

The reference publication EP 0 783 235 describes a method foridentifying the proximate location of a wireless terminal. As anapplication of such location identification, the publication mentionsthe possibility of offering position-related weather reports to theusers of wireless terminals. This is another example of knownapplications of location-dependent service profiles. The referencepublication FR 2 711 033 discloses the use of a location server whichspecializes in finding out the approximate locations of mobile stations.

BACKGROUND OF THE INVENTION

An object of the present invention is to provide a method and system formaking services provided by a network available to the user in variousways depending on the location of the user, without placing largerequirements to the network.

The objects of the invention are achieved by storing in the memory ofthe mobile station the information on the basis of which it recognizesthat it is situated in a given localized service area and by programmingthe mobile station such that in response to such recognition it sends anappropriate message to an apparatus that provides services.

The invention pertains to a communications system that comprises basestations to provide mobile stations with communications links and atleast one localized service area. It is characterized in that itcomprises a service server which is arranged to maintain informationconcerning the location of mobile stations in localized service areasand to generate requests for changing the service selection offered tomobile stations in response to receiving, from the mobile stations,mobile station generated messages describing the location of the mobilestations in relation to localized service areas, and means for changingthe service selection offered to a mobile station on the initiative ofthe communications system in response to an indication that the mobilestation has arrived in said localized service area.

The invention also pertains to a cellular mobile station that comprisesa control block and storage means. It is characterized in that itsstorage means are adapted so as to store the information required torecognize a given localized service area whereby the mobile station isarrange so as to send-in response to the recognition of a localizedservice area-a notification of its arrival in the localized servicearea, said notification being intended to function as an impulse forchanging the service selection offered to the mobile station.

The invention further pertains to a method for changing the serviceselection offered to a mobile station in a communications system thatcomprises base stations for providing mobile stations withcommunications links. The method is characterized in that it comprisessteps in which

-   from the mobile station there is received a message indicating that    the mobile station has detected that it is in the localized service    area-   information is generated about the arrival of a mobile station in a    localized service area, and-   the service selection offered to said mobile station on the    initiative of the communications system is changed.

In accordance with the invention, localized service areas (LSA) aredefined for mobile stations, which areas may be purely geographical ormay have some other criteria. In addition to or instead of thegeographical definition a localized service area may be defined e. g. inchronological terms. “Geographical definition” means generallydefinitions associated with a place or area: a localized service areamay comprise a base station cell, several cells, a location area (LA), apublic land mobile network (PLMN), an area defined by coordinates,certain cell identifiers, or an area in which base stations send tomobile stations some other identifier. Combinations of thesealternatives may be used, too.

Information about how a mobile station can recognize that it is in agiven localized service area is stored in the memory of the mobilestation. Since services are usually in a way or another associated withthe subscription contract in which the user is given certainuser-specific rights to use the communications network, it is preferableto store the information relating to the recognition of a localizedservice area in the user's SIM (subscriber identity module) card or acorresponding memory means intended specifically for the identificationof the user independent of the apparatus used. In response to a positiveidentification the user's mobile station sends a message addressed to anapparatus responsible for providing localized services in the network.With this message the mobile station tells that the user is in a certainlocalized service area. On the basis of the message the network canoffer to the user just those services that are needed in that localizedservice area. When the mobile station moves elsewhere, it sends asimilar message telling that it is leaving the localized service area.The network may also automatically deduce that the mobile station hasleft the area as a certain condition is met. Such conditions includee.g. that

-   the mobile station does not respond to the next paging message or    another message sent in the localized service area in question,-   the mobile station does not acknowledge a data packet addressed to    it,-   the mobile station does not in a certain period of time renew its    message of arrival in the localized service area, or-   the mobile station does not in a certain period of time send another    message that must be sent periodically, such as the periodic    location update (PLU) message, for example.

The apparatus, to which the mobile station addresses its locationmessage, may be maintained by the network operator or a serviceprovider. The message may be an SMS (Short Message Service) message, anunstructured supplementary service data (USSD) message, a DTNF-coded(Dual Tone Multi-Frequency) message sent in conjunction with an ordinarycall, or a data call. In response to the message the apparatus, to whichthe mobile station addresses its location message, may e. g. sendinformation about the area in question to the mobile station or startthe regular or periodic sending of such information, which goes on untilthe mobile station leaves the localized service area. Furthermore, theapparatus providing the services may activate or inactivate anotherlocalized service, send information about the location of the mobilestation to other apparatus which need that information in theiroperation, or carry out some other function. One option is that mobilestations are as-signed certain localized service profiles which maycomprise various factors from call pricing to data rates of data callsor to priorities of call establishment and management. The applicationof the service profile is in that case based on the location of themobile station in a given localized service area.

Other objects and features of the present invention will become apparentfrom the following detailed description considered in conjunction withthe accompanying drawings. It is to be understood, however, that thedrawings are intended solely for purposes of illustration and not as adefinition of the limits of the invention, for which reference should bemade to the appended claims.

The invention is below described in more detail with reference to thepreferred embodiments presented by way of example and to theaccompanying drawing in which

FIG. 1 shows a communications system according to the invention,

FIG. 2 illustrates the exchange of messages in the communications systemac-cording to FIG. 1,

FIG. 3 shows a second communications system according to the invention,

FIG. 4 shows a mobile station according to the invention, and

FIG. 5 shows an embodiment of the method according to the invention.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS

FIG. 1 shows a cellular radio system 100 which in a known mannercomprises base transceiver stations (BTS) 101, base station controllers(BSC) 102 and mobile switching centers (MSC) 103. A mobile station (MS)104 is connected via radio to at least one base transceiver station 101so that the system considers the mobile station to be located in thatlocation area (LA) 105 to which the coverage area, or cell, of thatparticular base transceiver station belongs. A location area maycomprise one or more cells. For the purpose of maintaining location dataof mobile stations and routing calls the system includes home locationregisters (HLR) 106 and visitor location registers (VLR) 107 whichusually are located at mobile switching centers. In the system accordingto FIG. 1 a service server (SS) 108 and application servers (AS) 109 arealso connected to the cellular radio network through wire links.Connections from the cellular radio network to servers 108 and 109 maybe either direct, in which case the servers are in a way part of thecellular radio system, or routed via the public switched telephonenetwork (PSTN) 110. Direct connections will be used mainly when servers108 and 109 are maintained by the same operator who is responsible forthe operation of the cellular radio system.

A prerequisite for the operation according to the invention is thatsomehow a piece of information is generated indicating that a mobilestation is located in a certain designated localized service area 111.As was mentioned above, a localized service area may be the same as agiven location area but nothing prevents from defining localized serviceareas completely differently; in FIG. 1 the localized service area 111includes base transceiver stations under two different base stationcontrollers. According to a first embodiment of the invention, however,a service area always comprises a certain cell or certain cells. If thecoverage area of a base transceiver station can by means of directionalantennas be divided into cells or blocks smaller than the central cellaround the base transceiver station such that the system can make alogical distinction between those cells or blocks, then these smallerareas can also be utilized in defining the localized service area. Theinformation about the location of a mobile station in a service area canthen be generated either at the mobile station, which is regarded as themore preferable embodiment, or in fixed parts of the system. Alimitation of the latter option is that since known cellular radiosystems maintain mobile station location data only with the accuracy ofa location area, defining a localized service area smaller than onelocation area would call for changes in the operation of the system.

Let us then assume that the information about the location of a mobilestation in a localized service area is generated at the mobile stationitself. To that end there exist several known methods which usually arebased on the fact that every base transceiver station in known cellularradio systems sends general control information that can be received inthe whole cell area and which e.g. comprises the unequivocal identifierof the base transceiver station or some other information characteristicof the base transceiver station. A method for detecting base stationspecific identifiers has been stored in advance in the mobile station.In the simplest case the memory of the mobile station stores a list ofthe identifiers of the base transceiver stations the cells of which makea particular localized service area. By comparing the receivedidentifier with the list in the memory the mobile station finds outwhether it is located in a certain localized service area. According toan alternative embodiment only a certain mask is stored in the memory ofthe mobile station so that the mobile station uses the mask to selectcertain characters from the base station specific identifier to beexamined. If the characters examined form or follow a certain patternthe base station cell belongs to a localized service area. An advantageof this embodiment is that if the communications capacity of thelocalized service area is increased by establishing a new base stationin the area, there is no need to separately send the identifier of thenew base station to each mobile station to which the localized servicearea has been assigned; it suffices that the masked characters in thenew base station identifier are the same as or corresponding to those ofthe other base stations in that localized service area.

According to a second embodiment of the invention a localized servicearea is not associated with base station cells but has certaingeographic coordinates. In this embodiment a mobile station may detectthat it is in a given service area e. g. in such a manner that each basestation sends together with the general control information informationabout the location of the base station in a geographic coordinatesystem. Having received the coordinates the mobile station may examinewhether the point indicated by the coordinates is located within alocalized service area assigned to the mobile station. In a moreversatile method the mobile station may receive coordinates from all thebase stations from which it can receive general control information, andassume that its own location is the average of the coordinates received.By comparing the location it has computed with the stored geographicdefinition of the localized service area the mobile station detectswhether or not it is in the localized service area. Future mobilestations may include a GPS (Global Positioning System) receiver or someother means completely independent of base stations to determine thelocation of the mobile station in a geographic coordinate system. Thismakes it possible to define a localized service area completelyindependent of the cellular radio system cells.

According to a third embodiment of the invention, temporal dimension isalso included in the definition of a localized service area. If acellular radio system comprises cells A, B, C, D and E, it can bedefined that a given localized service area comprises at all times cellsA and B, but cell C only between 12 and 3 o'clock in the afternoon, andcells D and E on Wednesday, Friday and Saturday from 6 p. m. till 3 a.m. in the next morning. Naturally the temporal dimension may also becombined with the cell-independent geographic definition describedabove.

FIG. 2 assumes that the information about the location of a mobilestation in a given service area is generated at the mobile station onthe basis of a base station specific identifier received by the mobilestation from the base station. The figure illustrates in a simplifiedmanner the exchange of messages relating to the operation according to apreferred embodiment of the invention between a mobile station 104, basetransceiver station 101, service server 108 and application server 109.The messages are depicted by arrows and their chronological order isfrom top down. Message 201 is a known general control informationmessage sent by the base station to the mobile station, comprising abase station specific identifier. General information messages includee. g. information sent by base stations on the broadcast control channel(BCCH) in the GSM system. Block 202 refers to the comparison at themobile station with an identifier list, or some other activity on thebasis of which the mobile station detects that it has arrived in acertain localized service area. In response to that observation themobile station sends to the service server a message 203 in which itincludes an identifier characteristic of the mobile station, say an IMSI(International Mobile Subscriber Identifier) code or MS-ISDN (MobileSubscriber Integrated Services Digital Network) number stored in the SIMcard of the mobile station.

The invention does not limit the form of message 203. One advantageousoption is to use an SMS message such that the mobile station reads fromthe memory the phone number of the service server and sends the SMSmessage to that number. A second option is to use a free-form datamessage specified in many digital cellular radio systems; in the GSM itis called an USSD message. The mobile station may also by itselfestablish a call connection to the service server and send the message203 DTMF-coded or as a data call.

The role of the service server in the embodiment according to FIG. 2 isto maintain information about which mobile stations are in whichlocalized service areas and which services should be offered to themaccordingly. The actual service is provided by the application server.Having received message 203 the service server reads from its memorywhich services should be offered to the mobile station in that localizedservice area and sends a service request 204 to the appropriateapplication server. The information about what services are provided bywhich application servers is also stored in the memory of the serviceserver so that it can send the service request 204 to the correctapplication server. The invention does not limit the form of the servicerequest 204. From the prior art it is known several methods forrealizing communication between two servers connected to acommunications network.

In response to a service request 204 the application server provides themobile station with a service, indicated in FIG. 2 simply by an arrow205. The service is not necessarily a simple message and itscommencement does not necessarily involve only information sent to themobile station. A mobile station may have a whole service profiledefined for it in a localized service area, including e. g.

-   call pricing or prioritization,-   limitations concerning the modulation method, data rate and/or    connection quality in the communication between the base station and    mobile station,-   routing of incoming email messages to a mobile station instead of    the user's desktop workstation, or-   activation or inactivation of automatic call transfer and/or voice    mail service.

The mobile station may also have the right or obligation in a givenlocalized service area to receive messages periodically e. g. withregard to the weather, traffic, stock exchange rates and so on. Thus theapplication server may at the stage represented by arrow 205 establishconnections in a versatile manner with various apparatus in the cellularradio system or in communication with the cellular radio system. On theother hand, the service server may have instructions stored in itsmemory to request services from more than one application server, inwhich case there would be several messages 204 sent to a plurality ofapplication servers.

FIG. 2 further assumes that the mobile station leaves the localizedservice area in accordance with controlled cell reselection in whichcase it sends to the service server a notification 206 about itsdeparture from the service area. In response to the departure messagethe service server sends to the application server a request 207 toterminate the service. The mobile station can send message 206 via theold base station always when leaving a cell belonging to the localizedservice area regardless of whether the new cell belongs to the samelocalized service area. In an alternative embodiment the mobile stationchecks always after a cell reselection whether it is still in the samelocalized service area, and if not, it sends via the new base station anotification about its departure to the service server. According to asecond alternative embodiment mobile stations do not send departuremessages at all but the departure of a mobile station from a givenlocalized service area is detected by fixed parts of the system e. g.when a mobile station will not respond to a paging message or anothermessage sent to it in that localized service area, or will not send thespecified periodic location update message or some other mandatoryperiodic notification, or when the service server sends regularly orperiodically to all mobile stations in a localized service area a shortdata message which must be acknowledged by the mobile stations; afailure to acknowledge the message indicates that the mo- bile stationin question is no more in the localized service area.

Above it was disclosed that in a given localized service area a mobilestation receives a certain service. However, service areas may bedefined which are characterized in that a mobile station will not beoffered a service that it would receive elsewhere. A mobile station maybe assigned several service areas with different operating instructionsfor the different areas. The service server which the mobile stationinforms about its arrival in a localized service area may be always thesame or different in some localized service areas. Alone the fact thatwhether or not a mobile station indicates its arrival in a localizedservice area and if so, how quickly it does it, may depend on theservice area. The user may be given a choice about whether or not togive notification about his arrival in a localized service area. Themobile station may even inform the user that he has now arrived in alocalized service area and ask for permission to send the notificationof arrival. In connection with the request for permission the user maybe given a short description of the con-sequences of sending thenotification of arrival. On the other hand, certain localized serviceareas may be defined by the network operator such that the notificationof arrival is compulsory, whereby a mobile station has to send anotification of arrival every time that it arrives in such a localizedservice area regardless of what the user instructs the mobile station todo.

Above it was disclosed that in a given localized service area a mobilestation receives a certain service. However, service areas may bedefined which are characterized in that a mobile station will not beoffered a service that it would receive elsewhere. A mobile station maybe assigned several service areas with different operating instructionsfor the different areas. The service server which the mobile stationinforms about its arrival in a localized service area may be always thesame or different in some localized service areas. Alone the fact thatwhether or not a mobile station indicates its arrival in a localizedservice area and if so, how quickly it does it, may depend on theservice area. The user may be given a choice about whether or not togive notification about his arrival in a localized service area. Themobile station may even inform the user that he has now arrived in alocalized service area and ask for permission to send the notificationof arrival. In connection with the request for permission the user maybe given a short description of the consequences of sending thenotification of arrival. On the other hand, certain localized serviceareas may be defined by the network operator such that the notificationof arrival is compulsory, whereby a mobile station has to send anotification of arrival every time that it arrives in such a localizedservice area regardless of what the user instructs the mobile station todo.

Above it was disclosed that the service server and application serverare separate apparatus. However, these functions can be integrated inone device, whereby the communication between the servers as describedabove is reduced to communication internal to a server. One or both ofthem may also be implemented in connection with a known apparatus thatalready belongs to the cellular radio system. Servers can advantageouslybe integrated in mobile switching centers or base station controllers.

FIG. 3 shows a communications system 300 according to the invention, inwhich a localized cellular service (LCS) 302 operates under a publicland mobile network (PLMN) 301 in an area with a high traffic density;the mobile switching center maintaining the service is called an LCSswitching center (LCS-SC) 303. The LCS-SC operates just like a prior-artmobile switching center. It provides for the internal communication ofthe LCS and establishes, maintains and terminates connections betweenterminal equipment in the LCS and elsewhere. In connection with theLCS-SC there is a visitor location register 304 and a combined serviceand application server 305, which is called simply a server. In thisembodiment of the invention the localized service area 306 covers allbase stations operating under the LCS-SC (for simplicity, the basestation controllers are not shown). Unlike above, the observation that agiven mobile station has arrived in the localized service area is madein the fixed parts of the network, more specifically in the visitorlocation register 304. Let the cellular subsystem shown in FIG. 3operate at an airport. Airline companies can provide the visitorlocation register 304 with the mobile phone numbers or other identifiersof their customers to whom certain benefits have been granted on thebasis of their being frequent flyers, for example. As the visitorlocation register 304 detects that a mobile station associated with suchan identifier has arrived in the area of the cellular subsystem, itsends appropriate information to the server 305. Instead of or inaddition to the visitor location register other fixed network apparatusmay take part in the sending of the message. In response to thisinformation the server 305 starts sending to the mobile stationannouncements which are intended only to privileged customers of theairline companies. The announcements are advantageously delivered as SMSmessages.

In known digital telephone systems the sending of SMS messages iscarried out via SMS service centers and not directly from an apparatusto another. However, for simplicity the SMS service centers are notincluded in the description above but their use is considered to beknown to a person skilled in the art. Other messages described above mayalso be sent between apparatus via various known intermediary devices.

FIG. 4 shows simplified a control block and some memory parts of amobile station according to the invention. The control block 401 ispreferably a microprocessor which is located in the mobile station in aknown manner such that data received by the mobile station, except fordata intended to be presented directly to the user, is conducted fromthe receiver chain RX to the control block and, correspondingly,outgoing data produced by the control block is conducted to thetransmitter chain TX of the mobile station together with the data comingdirectly from the user (say, digitized speech). In the mobile stationaccording to FIG. 4 the control block has access to a fixed memory 402and a removable memory unit 403, which is e. g. a smart card. Thecontrol block 401 also receives input from a keypad 404 and it outputsinformation on a display 405. A program executed by the control block401 is stored in the fixed memory 402. Part of that program is aninstruction to look for program extensions in the removable memory unit403. For the operation according to the invention the removable memoryunit includes a program 406 by means of which the mobile station is ableto utilize localized service areas, as well as information 407,408 aboutat least one localized service area (LSA1, LSA2). FIG. 4 assumes thatthe recognition of a localized service area is based on the mobilestation comparing received base transceiver station identifiers (BTS ID)with a list of localized service areas stored in the memory. For eachlocalized service area the re-movable memory unit 403 also includes aservice server identifier (SS ID).

FIG. 5 illustrates the principle of a method according to a preferredembodiment of the invention in a mobile station, service server andapplication server. In accordance with block 501 the mobile stationdetects a cell reselection. It examines, block 502, whether any changesare occurring with respect to localized service areas, i. e. whether itis arriving in a localized service area (if until now it wasn't in one)or if it is leaving a localized service area (if until now it was inone). In accordance with block 503 the change triggers the sending of amessage to a service server the operation of which starts from thereception of the message, block 504. According to block 505 the serviceserver examines whether the mobile station in question is on the list ofthose to be served. If the mobile station is arriving in a localizedservice area, it is in block 505 recognized as a mobile station which isto be served. If, on the other hand, the mobile station is leaving alocalized service area, it is recognized in block 505 as a mobilestation the services to which have to be terminated. A correspondingmessage is sent according to block 506 to an application server whichreceives the message in block 507 and determines in block 508 whetherthe message calls for the starting or termination of a service. Theservice is then either started 509 or terminated 510 for the mobilestation, whichever the case may be.

The embodiments of the invention described above are naturally examplesonly and do not limit the invention. Communications systems, to whichthe invention can be advantageously applied, include e. g.second-generation digital mobile phone systems such as the GSM and itsextensions, PDC (Personal Digital Cellular), D-AMPS (Digital AdvancedMobile Phone System) and PCS (Personal Communications Services) andfuture third-generation digital cellular radio systems such as the UMTS(Universal Mobile Telecommunications System) and IMT-2000 (InternationalMobile Telecommunications at 2000 MHz).

Thus, while there have been shown and described and pointed outfundamental novel features of the present invention as applied to apreferred embodiments thereof, it will be understood that variousomissions and substitutions and changes in the form and details of thedevices illustrated, and their operation, may be made by those skilledin the art without departing from the spirit of the present invention.For example, it is expressly intended that all combinations of thoseelements and/or method steps which perform substantially the samefunction in substantially the same way to achieve the same results arewithin the scope of the invention. Substitutions of elements from onedescribed embodiment to another are also fully intended andcontemplated. It is the intention, therefore, to be limited only asindicated by the scope of the claims appended hereto.

What is claimed is:
 1. A method comprising: detecting arrival at alocalized service area; determining to change data associated with aservice selection for the localized service area; and generating amessage indicating the determination to change the data.